[ECG changes following balloon dilatation of pulmonary valve stenoses].

To evaluate the role of electrocardiography in the long-term follow up of children after balloon valvuloplasty of pulmonary stenosis the ECG findings of ten children (4 girls and 6 boys) with a mean age of 7.8 +/- 3.3 years who underwent valvuloplasty of pulmonary stenosis were studied. There was a significant decrease of the gradient across the valve from 61.8 +/- 15.05 mmHg to 24.8 +/- 9.52 mm Hg (p less than 0.001). In all children ECGs were available before dilatation. The frontal plane mean QRS vector moved significantly (p less than 0.02) towards the left from 116.3 +/- 59.86 (67-[-120]) to 86.7 +/- 56.22 (30-[-142]) between three to six months. Further changes between 12 and 24 months after Balloon valvuloplasty of pulmonary stenosis were not significant (71.11 +/- 61.74 (30-[-133])). The sum of the amplitude of RV1 and SV6 (mV) decreased significantly (p less than 0.02) within three to six months from 2.13 +/- 0.64 (1.1-3.1) to 1.53 +/- 0.50 (1-2.3). Later changes within the following 12 to 24 months were not significant (1.2 +/- 0.31 (0.8-1.5)). Since these ECG changes parallel the decrease of the gradient across the pulmonary valve, this would suggest, that besides Doppler-echocardiography ECG seems to have a useful role in the long term follow up of children after valvuloplasty of pulmonary stenosis.